Normalization Method for the Evaluation of Ductile Fracture Behavior Using Small COEC Specimen

doi:10.3901/JME.2017.20.061

Abstract

Abstract: In the evaluation of fracture behavior of materials, specimen miniaturization not only has the advantages of convenient sampling and cost saving, but also has important engineering significance to special sampling requirements of fracture toughness test. According to non-dimensional load separation principle, the normalization method for estimating the fracture toughness of ductile materials using a C-shaped outside edge-notched compression (COEC) specimen are proposed. J-resistance curves tests for A508-III are carried out by use of COEC, compact tension(CT) and single edged-notched bending(SEB) specimens with different specifications, respectively. The results show that the initial crack size has evident influence on the fracture toughness of ductile materials obtained by COEC specimen, compared with the effect of specimen thickness. Meanwhile, due to the higher level of constraint near the crack tip of the COEC specimens, remarkable lower J-resistance curves can be observed in comparison with the results of the CT and SEB specimens.

Key words: cack tip constraint, COEC small specimen, ductile fracture toughness, non-dimensional load separation principle, normalization method

CLC Number:

O346

HE Guangwei, BAO Chen, CAI Lixun, ZHAO Xinghua. Normalization Method for the Evaluation of Ductile Fracture Behavior Using Small COEC Specimen[J]. Journal of Mechanical Engineering, 2017, 53(20): 61-68.

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